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Tekmar 150 thermostat replacement with a Tekmar 561

I am trying to replace my old Tekmar 150 thermostat with a new 561 WiFi one
the old Thermostat has these terminals on it C - RT - PWR - NO ( I am not use any floor sensors
New 561 Thermostat Has these Terminals - C - R - Away - RH1 - W1 -( I know that these last 3 are for the floor sensors sen com -S1 -S2 )

Can you please tell me which wire from the old thermostat goes on which terminal of the new thermostat
Thank you for your help


  • Big Ed_4
    Big Ed_4 Member Posts: 2,805
    If your radiation is radiant you want to use a Tekmar and you want the floor sensor . If you don't want a floor sensor or you don't have radiant , throw in a regular wifi ....

    There was an error rendering this rich post.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,025
    edited March 2023
    The 561 is designed to connect to the Tekmar ZVC1 zone control relays. I'm guessing you don't have one of those. I'm not sure where to put the AWAY wire on the control you have. Have you talked to Tekmar Tech support? I believe you have the wrong thermostat. It may or may not work with nothing connected to the AWAY terminal.

    If you want to try just connecting it to your existing control, I would need to know what that control is. The control that the thermostat wire goes to this way i can see if that control has a place to put the C wire.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    HVACNUT Member Posts: 5,857
    It doesn't need the ZVC1 but without the floor sensor, it's just a really expensive switch that will also tell you the weather. Put in the 501, or any thermostat that CPH can be adjusted.
    If the radiant is throughout the home and you would like to monitor it while away, I can understand the want for WiFi, but other than that, with radiant, you just set it and leave it alone.